Core Loss Model for Non-Sinusoidal Excitations Based on Vector Magnetic Circuit Theory

With the development of switching devices towards high frequency, the prediction and calculation of magnetic material losses under high frequency have become increasingly important. In order to calculate the magnetic core loss under arbitrary waveform excitation at high frequency, an analytical magnetic core loss calculation model is proposed based on the vector magnetic circuit theory, where Fourier decomposition on non-sinusoidal excitation is performed and the variation of magductance and hysteretance with frequency and magnetic flux density under sinusoidal excitation is taken into account. The accuracy and effectiveness of the proposed method has been verified by comparing the predicted and measured data of the magnetic core 3E6.

I. Introduction

In recent years, electric motor drivers are gradually developing towards miniaturization and high frequency along with the development of electric motors [1] Optimizing inductive components helps achieve objectives, such as increased efficiency, cost savings, and miniaturization of switched-mode power supplies [2]. In a high-frequency working environment, the core loss inside the inductor will increase nonlinearly. Therefore, accurate prediction of highfrequency core losses inside inductors helps in the design and optimization of electric motor drives [3]. However, such predictions remain a challenge as core losses depend on various factors, e.g., magnetic core material, size, magnetic flux density, frequency, and excitation type.